Subtotal: $0.00

No products in the cart.

No products in the cart.

Subtotal: $0.00

No products in the cart.

No products in the cart.

Table of Contents

Cannabis and Driving

Dani Walton
Dani Walton
Cannabis and Driving

In the study called Driving Performance and Cannabis Users’ Perception of Safety A Randomized Clinical Trial and Conducted by Thomas D. Marcotte, Anya Umlauf and David J. Grelotti where a specific analysis of cannabis users was made, some interesting results were obtained. For this reason, we are now going to review what this study tells us, which reveals very interesting things.

In a study with 191 regular cannabis users who were randomly assigned to smoke THC or placebo cigarettes as much as they wanted, we found that the group who smoked THC performed worse on a driving simulator test compared to the placebo group. This includes difficulties with divided attention tasks. This adds to the growing evidence that THC affects driving ability negatively. The impact was significant, with a medium effect size.

Cannabis and driving is a serious problem that needs to be addressed. Weed use can impair a driver’s ability to drive.

When people were instructed to smoke cannabis as they would at home to feel high, we found no significant differences in their driving performance or the amount of THC in their blood, based on the THC content of the cannabis. This supports the idea that the way people smoke (how deeply they inhale and how long they hold the smoke) is important.

There are concerns that products with higher THC content will lead to more risks on the road, but this study suggests that some users may smoke these products in a way that doesn’t lead to more impairment than products with lower THC content. However, it’s important to note that these findings may not apply to other methods of consuming cannabis, such as dabbing, vaping, and oral consumption, where it’s harder for people to control the amount they take.

Although a recent study suggests that users of concentrates may be able to control their consumption.

Cannabis and Driving

The group that smoked THC generally felt impaired and unsure about driving at 30 minutes. But after an hour and a half, they started to feel safer to drive, even though the driving simulator data showed they were still performing worse.

This time period may be the most dangerous because the people who smoked THC may believe they are okay to drive, even though they are not. This is an important issue for public safety, as the goal is to prevent impaired drivers from getting on the road and becoming a danger.

The results from 3.5 hours (Cohen d = 0.29) suggest that some people were still impaired, even though the group who smoked THC was no longer significantly different from the control group (P = .07). For most people, the negative effects of THC on driving were gone by 4.5 hours.

This is similar to what has been found in studies using cannabis with lower THC content. It’s possible that there may still be impairments in other abilities that were not measured, or that problems may become more noticeable during longer drives. But a recent study found no negative effects of THC on driving 4 to 5 hours after using it.

Even under our highly controlled conditions, there was no correlation between blood THC concentrations collected 15 minutes after smoking and simulator performance at 30 minutes or at any other time point.

In the real world, the time from intake to termination and subsequent blood collection varies widely, and the current findings suggest that laws based on blood THC concentrations cannot be supported by themselves. 34,44

THC O production
THC O production

Higher intensity of marijuana use in the past 6 months was associated with higher blood THC concentrations after smoking, but higher marijuana concentrations or worse driving performance compared to the low intensity group was associated with behavioral tolerance. Sexual development is consistent.

However, the current findings also suggest that higher-intensity users adapt tolerance by increasing THC exposure when indicated to a self-reported high, resulting in performance decrements similar to those of less intense users, and they are more likely to not reduce the risk of driving. The benefits of behavioral tolerance may be more pronounced in drug users who target specific symptoms (eg, pain) and maintain consistent dosage levels.

Finally, based on the distribution of the placebo group, approximately half of the THC group would be classified as impaired, suggesting that identifying those at greatest risk for impairment is not as simple as detecting recent use and remains an important public safety challenge. In particular, alcohol showed a more consistent linear effect between blood (alcohol) level and impaired driving, although here again there is significant variation in the relationship.

Final ideas about this study

In a placebo-controlled parallel study with regular cannabis users smoking ad libitum cannabis with varying levels of THC, driving simulator performance was statistically significantly worse in the THC group compared to the placebo group. THC content of marijuana and intensity of previous marijuana use were unrelated to driving performance; the way participants self-titrated resulted in a similar reduction in driving performance, despite achieving different THC blood concentrations.

The lack of awareness of impaired driving, especially after 90 minutes, is worrying, as users are likely to self-assess when they feel safe. Although performance improved after 3.5 hours, full recovery was not achieved until 4.5 hours after smoking. The fact that not all participants using THC met criteria for impairment highlights individual differences in the impairing effects of cannabis.


The lack of correlation between blood THC levels and driving performance raises questions about the validity of the law itself. When users self-monitor their intake, the level of harm cannot be inferred based on the product’s THC content, an individual’s behavioral tolerance level, or blood THC levels.

Future research should address factors such as individual biological differences, personal experience with cannabis, and methods of cannabis use associated with driving problems.

Is Cannabis Use Linked to Increased Car Accident Risk?

However, this is not the only study that has carried out an analysis of safety when driving under the influence of cannabis for the same reason, we are also going to refer in this guide to another investigation called “Cannabis, Impaired Driving, and Road Safety: An Overview of Key Questions and Issues”, conducted by Bruna Brands, Patricia Di Ciano, and Robert E. Mann. With some brief references from this study, we hope you can better understand what the effects of cannabis are when driving your car. Let’s see.

Is Cannabis Use Linked to Increased Car Accident Risk? Recent studies suggest that drivers who recently consumed cannabis are more likely to be involved in a car accident. Three meta-analyses have shown that the acute use of cannabis does increase the risk of car accidents, but more research is needed to understand the extent of the increase and the characteristics of these accidents.

Car Accident

The main issue that needs to be addressed is whether drivers who recently consumed cannabis are more likely to be involved in a car accident. Recently, there has been a consensus on this question, although early studies were not conclusive. In 1999, Bates and Blakely reviewed the evidence and found that there was no evidence that cannabis alone increased the risk of being responsible for fatal or hospitalization-worthy traffic crashes, and may even reduce those risks.

However, these conclusions were based on a limited number of studies with challenging methodologies. Since then, more research has been done using better methodologies and suggests that cannabis does increase the risk of car accidents. Three meta-analyses have shown this conclusion, although the extent of the increase varies. More research is needed to fully understand how cannabis might increase the risk of accidents and what characteristics these accidents have, as well as its impact on injury severity.

The impact of cannabis on road safety

A Study on Canada in 2012 The effects of cannabis on road safety have recently gained more attention, leading to the estimation of its impact. A study by Wettlaufer et al. estimated the number of deaths, injuries, and accidents, as well as the social costs, caused by driving under the influence of cannabis in Canada in 2012. The results showed that cannabis-attributed collisions resulted in 75 deaths, 4,407 injuries, and $1 billion in estimated costs. The majority of casualties and costs were from collisions involving young drivers, who are more likely to drive under the influence of cannabis.

Medical cannabis safe driving

A Concerning Gap in Literature. Despite the implementation of per se laws in many jurisdictions, medical cannabis users have challenged the idea that their driving is impacted by cannabis use. However, there has been little research specifically on the effects of medical cannabis use on driving.

The prevalence of medical cannabis use, with 13% of cannabis users using it for medical purposes, makes this gap in the literature concerning. It is estimated that over half of medical cannabis users have driven within 2 hours of using it and most believe there is either “no risk” or “slight risk” of driving after medical use of cannabis. Some believe that therapeutic cannabis users can drive safely after using the drug

Medical cannabis safe driving

Our research investigated the impact of medical cannabis use on driving. In our study, we found that medical users experienced a decrease in driving speed, similar to those observed in recreational users.

This suggests that regardless of the purpose for which cannabis is used, it impairs driving abilities and does not result in the development of a tolerance. Our findings also revealed an increase in THC levels in the blood after medical use of cannabis, with no evidence of tolerance when compared to recreational use. Therefore, it is crucial for medical cannabis users to exercise caution when driving after consuming cannabis for medical reasons.

CBD and driving

The composition of cannabis includes various elements, but cannabidiol (CBD) has received the most attention in research besides THC. Different strains of cannabis may have varying ratios of THC to CBD, potentially leading to the creation of strains that reduce the impact of THC on driving. A recent review of the effect of THC and CBD sprays on driving did not reveal any impairment in patients with multiple sclerosis who used the THC and CBD spray for their symptoms.

Approximately 80 to 90 percent of the respondents reported no change in driving ability after using the THC and CBD spray. This indicates that CBD may not affect driving abilities. However, these studies were observational and focused on THC and CBD combinations, no experiments have been done on the effects of CBD alone on driving.

A study was conducted to determine the impact of CBD on THC-induced driving impairments. The study had a crossover design, with participants vaping 11% THC, 11% THC and 11% CBD, or a placebo. The results showed that the combination of THC and CBD increased the SDLP to the same extent as THC alone, indicating that CBD does not impact THC-induced driving impairments.

However, there were no effects on headway for any of the conditions, but the combination of THC and CBD had a higher standard deviation of headway than the placebo.

CBD and driving

This provides some evidence that the combination of THC and CBD may negatively impact driving. It should be noted that this study used vaping as the method of consumption, and CBD is usually taken orally. Further studies are necessary, especially given the findings from observational studies and the investigation of the effects of THC and CBD combinations on cognition.

Another study analyzed the effects of different strains of cannabis with varying ratios of THC and CBD on driving. The results showed that the SDLP was increased after strains of cannabis with high THC or equal amounts of THC and CBD, but not after strains dominant in CBD. This implies that CBD does not affect driving and does not reverse the deficit observed after using cannabis.

Cannabis and driving is a serious concern, but it’s important to note that not all cannabis products contain THC, the psychoactive compound that causes impairment. CBD, a non-psychoactive compound found in cannabis, has been shown to have potential benefits for reducing anxiety, pain, and inflammation.

However, it’s important to note that even CBD products can contain trace amounts of THC, which could potentially lead to impairment. If you use CBD products, it’s important to be aware of the THC content and to wait several hours before driving to ensure that any potential effects have worn off. It’s always best to err on the side of caution and avoid driving if there is any potential for impairment.

The best CBD strain for a safe driving

Now we are going to leave you three recommendations for genetics that you can use, without putting your integrity at risk when driving. Although, we always recommend you consult a specialist so that you do not have problems with the law of your country and obviously driving.

CBD Strawberry (1:25) – Cannabis and Driving

CBD Strawberry (1:25) is a strain of cannabis that has a CBD to THC ratio of 1:25. It blooms in approximately 8 weeks and is best grown in a warm and sunny climate to achieve maximum yields when grown outdoors. For indoor cultivation, temperature and humidity control, proper lighting, and nutrient control can be applied. It can also be grown in a greenhouse with the use of climate and nutrient control systems.

CBD Strawberry (1:25)

CBD Strawberry 1:25 has a sweet and fruity flavor with an intense aroma of ripe strawberries. This strain is effective in treating conditions such as anxiety, stress, chronic pain, and inflammation. In terms of yield, indoor harvest can yield about 1.97 oz/ft2, while outdoor harvest can reach 12 oz/plant.

CBD Lemon Kush (1:25) – Cannabis and Driving

CBD Lemon Kush 1:25 is a marijuana strain with a high CBD content and a 1:25 THC:CBD ratio. This variety can be useful in treating ailments such as anxiety, chronic pain, inflammation, and insomnia. In terms of its flavors and aromas, Lemon Kush is known for its fresh and sweet lemon flavor, with notes of earth and kush. The dominant terpenes in this strain are limonene and caryophyllene, which are responsible for its lemon aroma and its analgesic and anti-inflammatory properties.

CBD Lemon Kush 1 30

The effects of CBD Lemon Kush 1:25 are typically relaxing and calming, without causing a “high” feeling due to its low THC content. This variety can produce yields of between 1.47 and 1.64 oz/ft2 and between 12 and 17 oz/plant outdoors. The flowering time of CBD Lemon Kush 1:25 is around 8-9 weeks.

Auto CBD Cheese – Cannabis and Driving

Auto CBD Cheese is an autoflowering marijuana strain with a balanced THC to CBD ratio, with approximately 3%-5% THC and 12%-15% CBD levels. This genetics takes a short growing cycle of around 65 days from germination to harvest. In indoor cultivation, yields of approximately 1.47-1.64 oz/m2 can be expected, while in outdoor cultivation, yields of approximately 14-17 oz/plant  can be expected.

CBD Auto Cheese

The effects of Auto CBD Cheese are balanced and relaxing, with a feeling of pain relief and stress reduction. Additionally, this variety is known for its mature cheese flavor, with notes of spices and herbs. In terms of cultivation, there is no clear advantage of growing this genetics indoor or outdoor, as both methods can provide good results if the proper techniques and equipment are used.

Strains featured in this article:

Dani Walton

Dani Walton is a highly accomplished cannabis expert and entrepreneur hailing from the Bay Area. With an impressive track record spanning over 20 years, Dani has amassed a wealth of experience in the cannabis industry. Her journey has taken her across the globe, as she traveled with the executive team of Harborside for more than 11 years, passionately advocating for the positive impacts of the cannabis plant.

During her tenure at Harborside, Dani excelled in managing wholesale and distribution for Harborside's farm, while also playing a pivotal role in the development of their in-house brand, Key. Following her departure from Harborside, Dani embarked on a new venture, co-founding NXTLVL, a women-owned concentrate delivery service that quickly gained recognition and Agris Farms. A beautiful 5 acre light dep farm located in Woodland, near Sacramento.

Her extensive knowledge encompasses the latest consumer trends, cannabis sales, extraction techniques, cultivation methods, new brands and products, as well as the evolving science of cannabis medicine. Recognized as a respected authority in the industry, Dani has served as a judge for esteemed cannabis competitions such as Chalice, High Times, Dab- A- Doo, The Organic Cup and The Emerald Cup. Her expertise and insights have been sought after by renowned publications and media outlets, including Forbes, The Guardian, The Independent, and many others.

With her remarkable background and unwavering commitment to advancing the cannabis industry, Dani Walton stands as a true pioneer and an influential figure in the field.

Read More Read Less

Related Articles

Explore our shop

Shopping Cart
Scroll to Top

Blimburn Seeds


Weed Blog